Anti Christian? There are wasn’t anything like that. No idea what you’re talking about. Christianity isnt mentioned in the books and this is no different. It is an epic between good and evil, so theres that similarity. But not sure what you saw to say that it’s anti Christian
Someone from a seminary and someone else from a Christian university say that while Christianity isn’t specifically mentioned in LOTR, is a Christianity based fantasy. Boromir and Gandalf are examples.
https://m.youtube.com/watch?v=sV9R5Z02GtE
However, the Amazon spin is not.
My interest in LOTR is that Tolkien invented an entire language, Elvish.